Last week the holidays broke my routine. As I head into the New Year, The Roof at the Bottom of the World has been launched, and I will all too soon be back to the professorial demands of my day job. My resolution for the New Year is to keep this blog going on a monthly basis, with postings on the first of the month, and what better send-off for 2012 than a short, illustrated lecture on the geology of the Transantarctic Mountains? If you do not know the Rock Cycle, a brief primer can be found at this link.
The present-day Transantarctic Mountains (TAM) arose about 40-50 million years ago, as West Antarctica extended and pulled away from East Antarctica, along a master fault located along the seaward side of the mountains. Perhaps not coincidentally, the trend of the TAM follows an old, rifted margin of East Antarctica along which a major mountain belt formed around a half billion years ago. Geologists call mountain-building episodes orogenies, and they give them names. This orogenic episode in Antarctica is called the Ross. As with most sequences of rocks associated with mountain building, the Ross suite of sedimentary rocks were mostly deposited in oceanic settings, in part associated with volcanic rocks, and accumulated prior to and during the mountain-building interval. These rocks were buried deeply and deformed. In the guts of the mountain belt, melting occurred and voluminous magmas rose up into the overlying sequences. Then the whole process shut down and the mighty mountain range was eroded deeply to its core with only a level plain remaining. Deciphering the complexities of the Ross mountain belt has been the primary focus of my research throughout my career.
Kukri is the name given to the erosion surface on the Ross orogenic belt. Between about 350 and 180 million years ago, a thick sequence of sedimentary rocks accumulated on the Kukri erosion surface. The so-called Beacon deposits were laid down mainly by rivers and streams. Ancient glacial deposits characterize the lower portion of the sequence, and a number of layers of coal occur higher up. The Permian seed fern, Glossopteris, and the Triassic mammal-like reptile, Lystrosaurus, date the sequence, and allow correlation with similar sequences of sedimentary rocks found throughout the continents of the southern hemisphere.
The Beacon sequence ends with a brief episode of profuse magmatism, associated with the beginnings of break-up of the supercontinent of Pangaea. Much of the magma intruded as tabular sheets (sills) between layers of the Beacon sediments.
The uplift of the TAM 40-50 million years ago has left no rock record within the mountains themselves; however, sediments in the Ross Sea, offshore of the mountains, record their history of erosion. The final geological event to produce bedrock in the TAM is eruption of the McMurdo volcanic suite. Volcanism has been active at a sprinkling of centers along the Victoria Land coast beginning about 20 million years ago, and continuing to the present-day in the active lava lake on the summit of Mt. Erebus, not far from McMurdo Station and Scott Base.

This photo encapsulates the geology of the Transantarctic Mountains with folded and intruded metamorphic rocks of the Ross orogenic belt capped by the Kukri erosion surface and overlain by Beacon sedimentary rocks, the thin, light-colored beds, which have been intruded by the dark layers of magma. Scale on the cliff is about 600 feet vertical.

The highest reaches of the TAM are flat-topped and blocky, owing to the nature of the horizontal bedding in the Beacon sediments. Mt. Blackburn at the back of the image is the highest summit on the east side of Scott Glacier. The prominant horizontal line below the summit is the Kukri erosion surface. Beneath that all of the rock is Ross granite.

With the exception of the thin band of Beacon sediments in the uplands at the horizon, all the outcrops in this image are Ross igneous and meatmorphic rocks.

The contacts between igneous and metamorphic rocks can be beautiful by virture of their complexity. Pegmatite Point, Duncan Mountains.

A typical exposure of Beacon sediments, Falla Formation on Mt. Falla.

Beacon sedimentary rocks intruded by dark, igneous rocks, south end of The Cloudmaker. Piedmont glaciers puddle out across the rocky flat, merging with Beardmore Glacier at the right edge of the image.

A steam cloud rises from the summit of Mt. Erebus, the active volcano on Ross Island. Castle Rock is the prominent plug in the foreground.

At the summit of Mt. Erebus is a crater within a crater. Within the inner crater a crusted lake of lava continuously convects, releasing steam and other vapors.

Gallery – CTAM Crevasses

Central TAM crevasses 1

Central TAM crevasses 2

Central TAM crevasses 3

Central TAM crevasses 4

Central TAM crevasses 5

Central TAM crevasses 6

Last year I brought in the New Year at the CTAM camp (short for Central Transantarctic Mountains camp.) I had several fantastic flights over extremely crevassed terrain. This week's gallery is a sampling. The first two images are of Beardmore Glacier, the third and fourth are of Nimrod Glacier, the fifth is of the northeast flank of Mt. Markham, and the sixth is a random image from the middle of nowhere at the edge of the East Antarctic Ice Sheet.

Landsat image of the McMurdo Sound area. (adapted from The Roof at the Bottom of the World)

As the ship Discovery sailed back from a voyage along the Great Barrier (Ross Ice Shelf), the commander of the expedition, Robert Falcon Scott, was eager to find a suitable cove to moor the ship for the winter. On February 8, 1903, skirting along the west side of Mt. Erebus (the active shield volcano on Ross Island,) Discovery rounded the tip of the long peninsula and found a small, protected bay backed by fast ice and shoreline. After weighing the pros and cons, Scott recorded in his journal, “On the whole to-night I feel like staying where we are.” In a saddle just inland of the point, the party constructed a large, square hut for storage, and two smaller ones for geomagnetic observations. From its mooring at Hut Point, Discovery commanded a view of Winter Quarters Bay encircled as it was by volcanic landforms, the most prominent being Observation Hill.

This image looks across Winter Quarters Bay from Hut Point, with Discovery moored at the point and the three huts constructed by the expedition in the foreground. Observation Hill is immediately out of the photo on the right. (Photo from Scott's book, The Voyage of the Discovery, 1905.)

What Scott did not know at the time was that the breakout of ice during the 1902-03 austral summer was particularly deep into McMurdo Sound. After being fast for two winters and nearly so for a third, he came to realize. Subsequently, Shackleton was stopped by fast ice in 1908 at Cape Royds, 20 miles north of Winter Quarters Bay, and Scott in 1911 at Cape Evans about eight miles south of Cape Royds.
At the start of the International Geophysical Year (IGY, 1957-58,) the US chose Winter Quarters Bay as the location of its main center of operations, naming it McMurdo Station. The station is situated at a unique and strategic site. The slip behind Hut Point has water deep enough to accommodate large supply ships and tankers. In the early summer the ice out from the station is hard and smooth from the previous winter’s freeze and allows the landing of wheeled aircraft. Whereas about five miles to the south and up a gentle rise one comes to the Ross Ice Shelf, where a prepared runway allows aircraft landings all season.
The construction of McMurdo Station was the responsibility of the Navy’s newly established Task Force 43 (nicknamed Operation Deep Freeze), under the command of Adm. George Dufek. Because the hillsides around Winter Quarters Bay are fairly steeply inclined, the first task of the Seabees was to bulldoze down from the hillsides any loose volcanic gravel they could find and with it built terraces where buildings could be constructed. The station evolved quickly. By 1970 when I first saw McMurdo, all of the principal buildings were in place, and most of these have not changed their footprint since then. All of the pipes for water and sewer are above ground and must be insulated and wrapped in heat tape. The hospital, the garages, the firehouse, the helicopter hangar, the command center, the field staging buildings, the NSF chalet, all of these have been there from early years. The dining area was redesigned in the 1990’s, and the outside of the building was painted blue over the old tan, but the store and rec rooms remained pretty much the same.

Sketch of changes to the terrain around Winter Quarters Bay between 1956 and 1993. The high landform at the right edge of the image is Observation Hill. Hut Point is in the left foreground. (Source: Antarctic Journal of the U.S., v. 28, no. 2, 1993.)

What has changed is the sleeping quarters. In 1970 most everyone slept in group quarters with toilets and showers down the hall. By the 1980’s a series of buildings were constructed to house the growing population of McMurdo. Since then the standard is a pair of shared bedrooms sharing a common sink, shower, and toilet. A new science building was opened in November 1991, providing much needed space for science projects at the base. The cargo yards and the yard for recycling seem only to get bigger every year.
The two views of McMurdo Station that follow were shot in January 1983 and January 2011. One notable difference is the buildings that housed the nuclear power plant half way up on the side of Observation Hill in the lower left of the 1983 photo are gone in the 2011 photo. When it was shut down in October 1972, the plant had a record of more than a decade of continuous service. Since then, McMurdo has been powered by petroleum, and of late by supplementary wind power. Note the presence of fuel tanks up the hill on the far side of McMurdo in the 1983 photo, and their removal by 2011, along with the addition of several new tanks in the foreground of the photo.

McMurdo Station from Observation Hill, January, 1983

McMurdo Station from Observation Hill, January, 2011.

Gallery: Crevasses

Crevasses 1

Crevasses 2

Crevasses 3

Crevasses 4

Crevasses are fractures that open in moving glacier ice. At slow rates of movement glaciers flow as ductile (or plastic) solids, moving smoothly down their gradient; however, if the rate of movement is too fast, the ice will behave as a brittle solid and crack. Each time the ice cracks, the amount of actual displacement is a millimeter or so, but compound these fractures over time and very wide openings may result. Typically, as a crevasse opens windblown snow sifts into the opening crack and lodges there. As the crevasse widens, the continuous addition of snow creates a bridge across a crevasse. A great variety of crevasse patterns are possible depending on local conditions, as demonstrated in this week’s gallery. All of these images are taken in the vicinity of Byrd Glacier.

Anyone who travels to the deep field in Antarctica experiences setting foot in places where no human previously has traveled. Even if several field parties have worked in an area, there are still many ridgelines, moraines, tributary glaciers, and drifts that are virgin surfaces with no footprints. I have always felt a certain thrill, along with privilege, good fortune, and satisfaction, when I see a new perspective and frame a camera shot of a new location. I have climbed many mountains in places other than Antarctica and have often wondered if I was the first to reach some lonely spot. But I could never be confident that some old prospector searching for gold or a herder chasing goats into high country had not previously climbed a ridge on which I was standing. In most of the Transantarctic Mountains, however, the travelers have been precious few, and those who have gone before have typically left maps and scientific reports of exactly where they went.
Nevertheless, I must admit that after thirteen expeditions to Antarctica, the excitement has faded somewhat. Now, what gives me an even greater thrill is the knowledge that I am standing exactly where members of a previous field party have been and I am gazing over the same vista. I imagine their approach and wonder how it felt to them to be the first. I feel a connection, especially when I discover a cairn left by a field party as a marker of its achievement, and sometimes even a written record of who the men were and what they did.
For instance, in the early seasons after the International Geophysical Year in the late 1950s and early 1960s, when topographers were scouring the Transantarctic Mountains to prepare their maps, they built cairns at many of their survey stations. Perhaps a half-dozen times over the years, I have come upon these robust, chest-high constructions built from whatever stone the bedrock offered. Invariably they are placed at some high point overlooking a spacious panorama. Some might say that they are blemishes on pristine wilderness, but to me any cairn is an apt monument to the human history of this frozen land.
The most memorable cairn I’ve found was left by Laurence Gould’s party on Supporting Party Mountain in 1929. This was the end point of a 600-mile traverse begun at Little America with pause at the mountain front when Byrd flew by on his historic flight to the South Pole, and thence eastward discovering new mountains as the party progressed. During the 1977–1978 field season, my party was working in the area to the north of Leverett Glacier. From Gould’s writings, we knew that his party had built a cairn at the summit of the mountain there at the easternmost reach of the exploration. In it Gould had left a note claiming the territory to the east of longitude 150 in the name of the United State of America. Five years later, a field party associated with the second Byrd Antarctic expedition, revisited the cairn at the beginning of a traverse up Scott Glaceer. We knew the leader, Quin Blackburn, had left a note of his own, copied Gould’s note, and carried the original back to him. I was determined not to miss this remnant of the heroic era, and planned a day of mapping that would include a climb to the summit of Supporting Party Mountain and to its cairn. We approached up the gentle north ridge, whereas Gould’s and Blackburn’s parties had climbed up the steep western spur. Because of the convexity of the ridgeline we did not see the cairn until we were almost on it. Then there it was—an alien sign of humanity in a lifeless landscape! We peered into the chinks between the rocks and spotted the treasure deep within.

Gould's cairn on Supporting Party Mountain

The proper construction of a cairn in which a record is left includes a stone that can be withdrawn so that the contents can be easily accessed, and indeed that was how this cairn was made. I carefully removed the doorway stone, reached in, and took out a colorful tin can that had once held dried oats for Gould’s party. Inside the tin were the penciled notes, written with precision and flare in a surprisingly steady hand, given that Blackburn must have written them either with a gloved hand or a bare hand stiffened by the cold. In addition, there were a bamboo splint and a broken thermometer, left as relics of their heroic traverse.
My group lingered by the cairn, looked out at the scene that Gould and Blackburn had beheld, discussed the route that they had taken to this spot, took photos as souvenirs, then replaced the notes, added our own, and descended the mountain.
(Excerpt from The Roof at the Bottom of the World.)

Gallery: Vanda Ice Cracks

Vanda cracks 1

Vanda cracks 2

Vanda cracks 3

Vanda cracks 4

Lake Vanda sits in the middle of Wright Valley, one of the ice-free valleys to the west of McMurdo Sound. The center of the lake is a permanently frozen plug of white ice. During the summer months, meltwater from glaciers at either end of Wright Valley pours into the lake, producing a broad moat of open water. During the winter this moat freezes with a clarity that allows one to peer many feet down into the azure blue of the ice. As temperatures deepen and the ice contracts, lacy fractures propagate through the upper reaches of the ice, begging to be framed and shot. Each of these images is approximately one foot across.

Lake Vanda, early November, 1975, is frozen tight, awaiting the deluge of the summer thaw. The blue ice margin is home to the ice cracks in the gallery.

In the field when it comes to the kitchen, Stump’s first rule is, “No Soap!” Remember that every ounce of water has to be made by melting snow on the Coleman stove. By the time that a party settles into a field camp, we already pretty much share our germ pool, and remain healthy in isolation. Soapy water requires rinsing. If you do not rinse completely, soap on the dishes of the next meal can cause gastric distress. The extremely dry air of Antarctica is hard enough on all but the oiliest of skin, but repeatedly putting hands in soapy water is a guarantee of dry, cracked knuckles and cuticles.
So the routine after a meal is that we wipe our plates with a paper towel, and then put a few tablespoons of boiling water on the plate. Swish it around with a finger to melt any grease and dissolve the remaining food, pour the bit down the sump hole, and dry with a clean paper towel. Voila! The dishes are ready for the next meal. Cook pots require a little more water generally, but the drill is the same. I tend not to cook much heavily fried food in the field, mainly due to the trouble of cleaning up.
Then there is the question of personal hygiene, of washing. Antarctica is a remarkably clean place. To be sure there is dirt down in the rocks on a moraine, and the Dry Valleys across from McMurdo Station are blanketed in soil and dirty glacial drift. But generally one encounters only ice, snow, and rock in the field. One doesn’t get dirty from without. Exceptions might be greasy hands from working on a snowmobile, or blackening of the face over time due to soot from poorly burning white gas. For these, a little soap might be appropriate, followed by a liberal coating of Corn Huskers Lotion or Bag Balm.
I find it desirable to go into the field with enough tee-shirts and tightie-whities to change about once a week, and enough socks to change somewhat more frequently than that. For the rest of it, I adopt a laissez-faire attitude, letting Nature take its course. In my experience, you itch for about a week, mainly on the head and back. Depending on how much you have been sweating while out on the slopes, you acquire the acrid odor of a locker room. But pungent sweat along with the itch passes after a week or so, and the body moves to the phase of funk. In the cook tent body odor is shared like the germ pool, unconsciously as the individuals ripen in the communal pew. A dose of athlete’s foot, however, can threaten the balance, especially if the victim is drying his/her socks in the shared space. As weeks go by the scent attains a rich fullness, but is barely noticed somewhere there in the background. The aura of the cook tent gives notice to the odorless interior of Antarctica, emphatically, that humans are there.
At the time of pick up our olfactory impact on the Herc crews was visible. We always made our first stop in McMurdo the mess hall, where we would chow down on freshies and someone else’s cooking, and let the rest of the room whiff the aura of the deep field from whence we had come. Finally, we would make it to our long awaited showers, alone and naked, hot and steamy, the pleasure of lathering all the crevices, washing away the grime, becoming odorless. It is hardly a reason not to shower for so long, but after that first shampoo one’s hair has the silkiest, smoothest body, conditioned au naturel in pure funk.
My parting shot is this. One slow news day in the late 1970’s I was enjoying a phone interview with a sweet, young reporter from the Mesa Tribune who was asking about my Antarctic research. At some point toward the end I allowed that after nine weeks without a bath one gets pretty. The next morning on the front page of the Tribune was the banner, “ASU PROFESSOR “GETS FUNKY” ON THE ANTARCTIC TUNDRA.” It gave me pause.
Although she did get the first part right, I am still looking for tundra in the Transantarctic Mountains.

Gallery: Drifts

Drift 1

Drift 2

Drift 3

Drift 4

Drift 5

One of the most enduring features of the landscape of the Transantarctic Mountains is the drift. Because prevailing winds are so consistent, long, graceful drifts accumulate at many places in the lee of ridges and summits. These features are so persistent in the perpetually frozen climate of Antarctica, that the white snow of the crest of a drift typically gives way to solid, blue ice in its lower portion.

Perhaps the best way to begin this blog is to tell how I came to do research in the Transantarctic Mountains. I was leaving grad school at Yale in the spring of 1970, under a cloud, when I said to my mentor, Dick Armstrong, that I was fed up with academia and wanted “to get as far away as possible.” Dick’s response was, “Why don’t you try Antarctica?” and he gave me a list of names at universities that had recently been funded for geological research in the Transantarctic Mountains. Several responses pointed me toward Ohio State, which had just landed a large grant from the National Science Foundation (NSF). The centerpiece of the proposal had been to search for new localities of vertebrate fossils, like the ones found the season before at a place called Coalsack Bluff. But the proposal also included grad students to study each of the major rock groups in the area, and I was chosen to cover the suite of metamorphic rocks.
We were situated at a remote camp in the Transantarctic Mountains, around 600 miles south of McMurdo Station (the main US base on the continent) served by three Huey helicopters, flown and maintained by Navy personnel of VXE-6. The helos had a range of 100 miles, and we occupied two camps, so our coverage was 300 miles of the Transantarctic Mountains. To me, the situation was astounding. A typical work day would be fly out to some remote spot, be left with survival gear, hike and climb around in the mountains all day recording geology and collecting rocks, and then be picked up and flown back to the camp for dinner.
I had grown up in rural, central Pennsylvania steeped in the Appalachians, a lover of mountains, their wildness, their hidden recesses, their vistas, their strenuous demands. It was one of the main reasons that I had chosen to go into geology. By 1970, I had been west several times, had done Geology Field Camp in the Tobacco Root Mountains of western Montana, but beyond that, mountain belts like the Alps, the Himalayas, and the Andes, were all dreams. From regional geology classes and poring over globes, I knew of the Transantarctic Mountains, but they were so obscure that they had never remotely figured in any of my dreams.
The reality of working in the Transantarctic Mountains was profound. I had never experienced such pristine wilderness. I remember thinking how clean the place was. The landscape was stark and lifeless (an Ahem! here from the microbial biologists), an alien world of ice and rock and wind, fundamental Nature arrayed in the most beautiful shapes and patterns. The research opportunity, too, was amazing, with geological field mapping as the primary activity for data collection, and a virgin region where every day I reached places that no one had set foot before. By the time I returned from Antarctica (from “the Ice” as Antarcticans like to say), I was obsessed with going back.
Suffice it to say that I did make it back, and have continued to do so intermittently over the past 40 years. The patron of my research for all these years has been the National Science Foundation (NSF), specifically the Office of Polar Programs (OPP), which administers the U. S. Antarctic Program (USAP). I have only good things to say about NSF, but should make the disclaimer up front that the opinions expressed in this blog are mine, and do not necessarily reflect those of the National Science Foundation. Research in Antarctica is focused in a variety of fields besides geology, including astrophysics, glaciology, biology, and ocean and atmospheric sciences, with many projects these days having an emphasis in climate studies. The logistics that run the program are an integral part of everyone’s research, and a fascinating subject on their own.
As I move forward with this blog my intention is to recount what it has been like to do fieldwork in the Transantarctic Mountains, the camp life, the logistics of being there, climbing mountains, crossing paths of early explorers, the geology, Nature writ large. Each posting will also include a gallery of several images related by a theme.

Gallery: Ice Puddles

Ice puddle 1

Ice puddle 2

Ice puddle 3

Ice puddle 4

This week’s gallery contains images of what I call “ice puddles.” The ones pictured here formed on the side of a stream at the foot of the Duncan Mountains that was active around the solstice. When midday sunshine warmed rocks of an ice-cored moraine enough to cause melting, the stream babbled by our base camp. The puddles at the side of the stream filled and began to freeze, capturing bubbles beneath the ice. At night when the sun was low, the melting stopped and the stream dried up. The puddles drained, and the expanding airspace beneath the ice traced a series of momentary stands of the air/water/ice interface. The thickness of ice in these images is about 1/4 inch. The polygonal pattern on the final image outlines individual ice crystals, etched by the ablation (evaporation) of H2O molecules at the crystal boundaries.